Field: treatment of tailings, for example tailings from tailings ponds resulting from oil sands production. In oil sands production, bitumen may be extracted from a mixture that is approximately 10% bitumen, 80% sand, and 10% fine tailings. The fine tailings are generally deposited in a tailings pond. However, fine tailings will not fully settle in these tailing ponds. It is believed that the electrostatic interactions between the suspended particles, which are still partly contaminated with hydrocarbons, prevent this from occurring. These tailing ponds have become an environmental liability for the companies responsible.
The oil sands tailings ponds constitute an unanticipated but persistent environmental and economic problem. They reflect process deficiencies in the bitumen extraction methods currently used. The problem has been mitigated by the industries to some degree, but there are several ponds that still present a major challenge for reclamation. Recent studies have been published that address the treatment of tailings as they are produced, in order to avoid the need for the large settling and storage areas.